In the process of improving your applications, you will eventually come across a term like API (Application Programming Interface). It is impossible to imagine modern development without APIs. This term has many definitions, but we will try to explain it as simply as possible. API is like an open language, the rules of which are shared by a certain service. You can teach your application the rules of this language, so it can communicate with the service and access all the functions and data that the service is ready to share.